Assessing Social Value in Economic Evaluation to Scale up Novel TB Drug Regimens The goal of the proposed 3-year interdisciplinary multi-method project is to develop an innovative methodology to enhance traditional economic evaluation, using novel drug regimens for tuberculosis (TB) as a paradigm case. Over 400,000 people living with HIV (PLHIV) die of tuberculosis (TB) every year, accounting for 25% of the world's HIV-related deaths, most of them in low-income countries. TB treatment has changed little since the 1980s, requiring months of burdensome, often-toxic therapy. Prospects for developing novel TB drug regimens to alleviate treatment-induced suffering, however, are more promising now than at any time in the past 40 years. The emergence of novel TB drug regimens presents policymakers with decisions of far-reaching consequence regarding which novel regimens to implement at the population level (that is, to scale up) in specific settings. Economic evaluation is a critical component of the scale-up decision-making process for novel TB drug regimens. The most common form of economic evaluation is cost-effectiveness analysis (CEA). Traditional CEA compares the costs of interventions against health outcomes such as lives saved, years of life gained, or disability-adjusted life years (DALYs) averted. To be sure, such considerations have ethical importance, but decision-making processes that focus narrowly on them will deliver recommendations that fail to account for other human concerns of comparable ethical importance. This is a longstanding general problem in the ethics of health policy. A powerful ethical critique targets the inability of traditional CEA to incorporate central elements f social justice. Moreover, CEA does not take into account the perspectives of key stakeholders such as patients and healthcare providers, yet without their support no health intervention can be successfully scaled up. Our proposed methodology will enable decision makers to assess incremental social value - an innovative measure incorporating not only traditional cost-effectiveness analysis, but also norms of social justice and key stakeholders' perspectives - for a range of promising novel TB drug regimens. We will develop this methodology by accomplishing 3 specific aims: (1) using philosophical methods, we will demonstrate how to quantify the greatest gains or losses to social justice posed by the scale-up of novel TB drug regimens in a range of settings where the poorest members of society are most burdened by TB, often together with HIV; (2) using empirical data collection with patients, healthcare providers, and public health policymakers in 3 HIV-endemic, high TB-burden settings, we will demonstrate how to incorporate data on stakeholders' perspectives into economic evaluation; and (3) using formal modeling techniques, we will develop a flexible decision analysis model so that users can plug and play, inserting parameters that reflect their settings and obtaining locally relevant assessments of incremental social value. Our overarching objective is to support scale-up decision-making processes (with potential application to research program design as well) that are more ethically responsible than they would be using traditional CEA.